BACKGROUND
[0001] The present disclosure relates generally to icing conditions and, in particular,
to simulating icing conditions. Still more particularly, the present disclosure relates
to a method and apparatus for simulating icing conditions in which supercooled large
drops are present.
[0002] In aviation, icing on an aircraft may occur when the atmospheric conditions lead
to the formation of ice on the surfaces of the aircraft. Further, this ice also may
occur within the engine. Ice formation on the surfaces of the aircraft, on inlets
of an engine, and other locations is undesirable and potentially unsafe for operating
the aircraft.
[0003] Icing conditions may occur when drops of supercooled liquid water are present. In
these illustrative examples, water is considered to be supercooled when the water
is cooled below the stated freezing point for water but the water is still in a liquid
form. Icing conditions may be characterized by the size of the drops, the liquid water
content, the air temperature, and/or other parameters. These parameters may affect
the rate and extent at which ice forms on an aircraft.
[0004] Drops of water may be supercooled in various environments. For example, drops of
water may be supercooled in stratiform clouds and in cumulous clouds.
[0005] When icing occurs, the aircraft may not operate as desired. For example, ice on the
wing of an aircraft will cause the aircraft to stall at a lower angle of attack and
have an increased drag.
[0006] Aircraft may have mechanisms to prevent icing, remove ice, or some combination thereof
to handle these icing conditions. For example, aircraft may include icing detection,
prevention, and removal systems. Ice may be removed using bleed air, infrared heating,
and other suitable mechanisms.
[0007] Aircraft may have sensor systems designed to detect icing conditions. As new regulations
are developed with respect to icing conditions that should be detected, manufacturers
design and test sensor systems for detecting the icing conditions. For example, aircraft
may be required to be certified to operate in normal icing conditions and in supercooled
large drop icing conditions.
[0008] In designing and testing sensor systems, currently available test environments may
not provide an ability to simulate supercooled large drop icing conditions in the
manner desired to test new sensor systems. Therefore, it would be desirable to have
a method and apparatus that takes into account at least some of the issues discussed
above as well as possibly other issues.
[0009] JP H04 69539 describes a liquid microparticle generating apparatus suitable for an icemaking ice
tunnel performing an icing test of an aircraft or the like.
[0010] JP H04 70535 describes an aircraft test wind tunnel for testing using a model of an aircraft.
[0011] US 3111842 describes a wind tunnel for making aerodynamic tests.
SUMMARY
[0012] In one aspect, there is provided an icing simulation system as defined in claim 1.
In another aspect, there is provided a method as defined in claim 7.
[0013] In one illustrative example, an icing simulation system comprises a wind tunnel,
a nozzle system, and a controller. The nozzle system is configured to spray drops
of water within the wind tunnel. The controller is configured to control a number
of properties of the water in the nozzle system such that the nozzle system sprays
the drops of water with different sizes for a desired type of icing condition.
[0014] In another illustrative example, a method for simulating a desired type of icing
condition in a wind tunnel is present. A number of properties is controlled for water
sent to a nozzle system. The number of properties is controlled such that drops of
the water have different sizes associated with the desired type of icing condition.
The drops of water are sprayed from the nozzle system in the wind tunnel. The drops
of the water sprayed by the nozzle system have different sizes for the desired type
of icing condition.
[0015] The features and functions can be achieved independently in various embodiments of
the present disclosure or may be combined in yet other embodiments in which further
details can be seen with reference to the following description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The novel features believed characteristic of the illustrative embodiments are set
forth in the appended claims. The illustrative embodiments, however, as well as a
preferred mode of use, further objectives, and features thereof will best be understood
by reference to the following detailed description of an illustrative embodiment of
the present disclosure when read in conjunction with the accompanying drawings, wherein:
Figure 1 is an illustration of a block diagram of an icing simulation environment in accordance
with an illustrative embodiment;
Figure 2 is an illustration of a block diagram of properties controlled by a controller in
accordance with an illustrative embodiment;
Figure 3 is an illustration of a block diagram of a nozzle system in accordance with an illustrative
embodiment;
Figure 4 is an illustration of a block diagram of an infrastructure in an icing simulation
system in accordance with an illustrative embodiment;
Figure 5 is an illustration of an icing simulation system in accordance with an illustrative
embodiment;
Figure 6 is an illustration of a spray bar balancing system in accordance with an illustrative
embodiment;
Figure 7 is an illustration of a flowchart of a process for simulating icing conditions in
accordance with an illustrative embodiment;
Figure 8 is an illustration of a flowchart of a process for calibrating an icing simulation
system in accordance with an illustrative embodiment;
Figure 9 is an illustration of a data processing system in accordance with an illustrative
embodiment;
Figure 10 is an illustration of an aircraft manufacturing and service method in accordance
with an illustrative embodiment; and
Figure 11 is an illustration of an aircraft in which an illustrative embodiment may be implemented.
DETAILED DESCRIPTION
[0017] The illustrative embodiments recognize and take into account one or more different
considerations. For example, the illustrative embodiments recognize and take into
account that currently available systems for simulating icing conditions are unable
to simulate supercooled large drop icing conditions. In particular, the illustrative
embodiments recognize and take into account that simulating this type of icing condition
involves generating drops of water having two ranges of sizes. These ranges may be
two different distributions of water drop sizes. This type of distribution may take
the form of a supercooled large drop bimodal distribution.
[0018] For example, the illustrative embodiments recognize and take into account that currently
available wind tunnels used to simulate icing conditions are unable to generate drops
of water having the two ranges of sizes for supercooled large drop icing conditions.
[0019] Thus, one or more illustrative embodiments provide a method and apparatus for simulating
icing conditions. In one illustrative embodiment, an icing simulation system comprises
a wind tunnel, a nozzle system, and a controller. The nozzle system is configured
to spray drops of water within the wind tunnel. The controller is configured to control
a number of properties of the water in the nozzle system such that the nozzle system
sprays the drops of water with different sizes for a desired type of icing condition.
[0020] With reference now to the figures and, in particular, with reference to
Figure 1, an illustration of a block diagram of an icing simulation environment is depicted
in accordance with an illustrative embodiment. In this illustrative example, icing
simulation environment
100 may be used to simulate types of icing conditions
102.
[0021] In particular, types of icing conditions
102 may be simulated for test object
103. Test object
103 may be, for example, structure
104, platform
106, or both. Structure
104 may be a structure in platform
106. When platform
106 takes the form of aircraft
108, structure
104 may be a structure in aircraft
108. For example, structure
104 may be a wing, a horizontal stabilizer, a vertical stabilizer, an engine, a landing
gear system, a fuselage, a flap, an aircraft windshield, or some other suitable structure.
[0022] In one illustrative embodiment, icing simulation system
110 may be used to simulate desired type of icing condition
111 in one or more of types of icing conditions
102 for test object
103. Desired type of icing condition
111 is a type of icing condition for which testing is desired with respect to test object
103.
[0023] In particular, icing simulation system
110 may be used to simulate desired type of icing condition
111 as first type of icing condition
112, second type of icing condition
114, or both.
[0024] In these illustrative examples, first type of icing condition
112 and second type of icing condition
114 in types of icing conditions
102 may differ from each other based on drop size. The drop size may differ based on
a mean volumetric diameter. More specifically, the drop sizes may differ based on
ranges of sizes. In other words, first type of icing condition
112 may have one range of sizes, and second type of icing condition
114 may have another range of sizes. The distribution of sizes within the ranges also
may be used to define different types of icing conditions.
[0025] In these illustrative examples, first type of icing condition
112 may be present when the size of the drops is from about 0.00465 millimeters in diameter
to about 0.111 millimeters in diameter. Drops with these sizes may be referred to
as normal drops.
[0026] Second type of icing condition
114 may be present when the size of the drops includes drops that have a diameter greater
than about 0.111 millimeters. Drops having a size greater than about 0.111 millimeters
may be referred to as large drops and, in particular, may be called supercooled large
drops under the altitude, temperature, and liquid water content conditions described
above. For example, the drops may have a diameter in a range from about 0.112 millimeters
to about 2.2 millimeters. In addition, second type of icing condition
114 may include drops that are 0.111 millimeters or less when drops greater than 0.111
millimeters are present. In other words, second type of icing condition
114 includes both normal drops and large drops of water.
[0027] In simulating desired type of icing condition
111, liquid water content in the drops may also be used to characterize the type of icing
condition. For example, first type of icing condition
112 may have liquid water content in the range of about 0.04 grams per cubic meter to
about 2.8 grams per cubic meter. On the other hand, second type of icing condition
114 may have liquid water content in the range of about 0.19 grams per cubic meter to
about 0.44 grams per cubic meter.
[0028] In the depicted examples, icing simulation system
110 is a physical system that also may include software. Icing simulation system
110 includes wind tunnel
116, air drive system
118, cooling system
120, nozzle system
122, sensor system
123, water source
124, air source
126, infrastructure
127, controller
128, and other suitable components.
[0029] As depicted, air drive system
118 causes air
129 to flow within wind tunnel
116. Cooling system
120 may cool the temperature of air
129 within wind tunnel
116.
[0030] Infrastructure
127 comprises components that carry water
130 and air
134 to nozzle system
122. In particular, infrastructure
127 connects water source
124 and air source
126 to nozzle system
122. Additionally, infrastructure
127 also may be connected to cooling system
120. The connection to cooling system
120 may be used to cool water
130, air
134, or both. Additionally, infrastructure
127 also may be connected to cooling system
120. The connection to cooling system
120 may be used to cool water
130, air
134, or both.
[0031] Nozzle system
122 receives water
130 from water source
124 through infrastructure
127 and generates drops
132 of water
130. In other words, drops
132 of water
130 are generated by water
130 flowing through nozzle system
122.
[0032] In some illustrative examples, air
134 received through infrastructure 127 may be introduced into water
130 as water
130 flows through nozzle system
122 to form drops
132 of water
130. In these illustrative examples, air source
126 also may send air
134 to nozzle system
122 via infrastructure
127. Within nozzle system
122, air
134 may be mixed with water
130 to form drops
132 of water
130 sprayed by nozzle system
122.
[0033] In these illustrative examples, drops
132 of water
130 generated by nozzle system
122 may have properties
136 to simulate first type of icing condition
112, second type of icing condition
114, or both. In these illustrative examples, properties
136 of drops
132 of water
130 may include, for example, without limitation, size, water content, temperature, and
other suitable properties.
[0034] Sensor system
123 is configured to generate data about one or more of properties
136 of drops
132 of water
130. In other words, sensor system
123 identifies properties
136 of drops
132 of water
130 generated by nozzle system
122 within wind tunnel
116.
[0035] Controller
128 is configured to control properties
140 of water
130 to simulate at least one of first type of icing condition
112, second type of icing condition
114, or both.
[0036] Controller
128 may use data from sensor system
123 to adjust values for a number of properties in properties
140 of water
130 to obtain desired type of icing condition
111 within types of icing conditions
102. In other words, sensor system
123 provides feedback to controller
128 about drops
132 of water
130. The data received from sensor system
123 may be used to adjust properties
140 of water
130 if properties
136 for drops
132 of water
130 do not have desired values for desired type of icing condition
111.
[0037] The adjustment of properties
140 of water
130 made by controller
128 may be made at different times during testing. For example, the adjustment may be
made prior to placing test object
103 into wind tunnel
116 for testing of desired type of icing condition
111. Additionally, these adjustments may be made while the simulation of desired type
of icing condition
111 is performed on test object
103. In other words, adjustments may be made dynamically during the testing to maintain
desired type of icing condition
111.
[0038] In these illustrative examples, controller
128 is comprised of hardware, software, or both. For example, controller
128 may be a computer system. The computer system may include one or more computers.
When more than one computer is present in the computer system, those computers may
be in communication with each other through a network. In other illustrative examples,
controller
128 may be implemented using hardware with circuits configured to perform operations
to simulate types of icing conditions
102.
[0039] In these illustrative examples, the hardware may take the form of a circuit system,
an integrated circuit, an application specific integrated circuit (ASIC), a programmable
logic device, or some other suitable type of hardware configured to perform a number
of operations. With a programmable logic device, the device is configured to perform
the number of operations. The device may be reconfigured at a later time or may be
permanently configured to perform the number of operations. Examples of programmable
logic devices include, for example, a programmable logic array, a programmable array
logic, a field programmable logic array, a field programmable gate array, and other
suitable hardware devices. Additionally, the processes may be implemented in organic
components integrated with inorganic components and/or may be comprised entirely of
organic components excluding a human being.
[0040] As depicted, test object
103 may be placed in test area
142 in wind tunnel
116 for exposure to drops
132 of water
130. By controlling properties
140 for water
130, drops
132 of water
130 may be generated by properties
136 to simulate desired type of icing condition
111.
[0041] This simulation of desired type of icing condition
111 may be used to determine how test object
103 may function. For example, test object
103 may be an airfoil with sensors configured to detect icing conditions. By simulating
desired type of icing condition
111, a determination may be made as to whether the sensors are able to detect desired
type of icing condition
111. In these illustrative examples, desired type of icing condition
111 may be a supercooled large drop icing condition.
[0042] Turning now to
Figure 2, an illustration of a block diagram of properties controlled by a controller is depicted
in accordance with an illustrative embodiment. Examples of properties
140 of water
130 that may be controlled by controller
128 to obtain properties
136 for drops
132 to simulate desired type of icing condition
111 in types of icing conditions
102 in
Figure 1 are shown in this illustrative example.
[0043] In these illustrative examples, properties
140 include at least one of water pressure
202, air pressure
204, air flow
206, temperature
208, and other suitable properties. Properties
140 controlled by controller
128 may be selected from one or more of properties
140.
[0044] Water pressure
202 is the pressure of water
130 in nozzle system
122 in
Figure 1. Air pressure
204 is the pressure of air
134 introduced into nozzle system
122. Air flow
206 is the speed at which air moves within wind tunnel
116. Temperature
208 is the temperature of water
130 in nozzle system
122. Temperature
208 may be selected to be near or below freezing for water
130 prior to water
130 being sprayed as drops
132 from nozzle system
122. The selection of temperature
208 is such that water
130 does not freeze within nozzles in nozzle system
122.
[0045] In these illustrative examples, values for at least one of water pressure
202, air pressure
204, and air flow
206 of properties
140 may be selected to obtain properties
136 of drops
132 that are desired for desired type of icing condition
111. These properties may include at least one of, for example, without limitation, size,
water content, temperature, and other suitable properties for drops
132 of water
130 in a manner that produces desired type of icing condition
111 in types of icing conditions
102.
[0046] The values for properties
140 may change, depending on the particular type of icing condition in types of icing
conditions
102. In other words, the values of properties
140 selected for first type of icing condition
112 are different from the values of properties
140 selected for second type of icing condition
114.
[0047] For example, air pressure
204 may be from about 10 psi to about 60 psi, and water pressure
202 may be from about 20 psi to about 240 psi. This combination of air pressure
204 and water pressure
202 may produce water drops having sizes of up to about 0.050 millimeters. The size of
the water drops may be increased by changing the pressure of the water relative to
the pressure of the air.
[0048] For example, air pressure
204 may be changed by a magnitude relative to water pressure
202. For example, water pressure
202 may be about 80 psi, and air pressure
204 may be about 8 psi. With this setting, the drops of water may be about 0.500 millimeters.
[0049] In some illustrative examples, air pressure
204 may be from about 10 psi to about 60 psi. Water pressure
202 may be from about 10 psi to about 240 psi. Of course, the values of water pressure
202 and air pressure
204 may change, depending on the types of nozzles used.
[0050] With reference now to
Figure 3, an illustration of a block diagram of a nozzle system is depicted in accordance
with an illustrative embodiment. Examples of components for nozzle system
122 are illustrated in this figure.
[0051] As depicted, nozzle system
122 is comprised of groups of nozzles
300 and support structures
301. In these illustrative examples, a group of nozzles within groups of nozzles
300 includes one or more nozzles. Further, one group of nozzles within groups of nozzles
300 may have a different number of nozzles than another group of nozzles within groups
of nozzles
300.
[0052] Support structures
301 are configured to be associated with groups of nozzles
300. When one component is "associated" with another component, the association is a physical
association in these depicted examples. For example, a first component, group of nozzles
304 in groups of nozzles
300, may be considered to be associated with a second component, support structure
306 in support structures
301, by being secured to the second component, bonded to the second component, mounted
to the second component, welded to the second component, fastened to the second component,
and/or connected to the second component in some other suitable manner. The first
component also may be connected to the second component using a third component. The
first component may also be considered to be associated with the second component
by being formed as part of and/or an extension of the second component. Further, the
association may be a temporary association in which the first component may be removed
from the second component or vice versa.
[0053] Support structures
301 may also be configured to receive water and direct water to groups of nozzles
300. In these illustrative examples, support structures
301 may include lines, valves, or other components that may be used to control the flow
of water within support structures
301. In some illustrative examples, support structures
301 also may include sensors used to generate data about water flowing through support
structures
301.
[0054] As depicted, the association of groups of nozzles
300 with support structures
301 forms plurality of spray bars
302. Each group of nozzles in groups of nozzles
300 is associated with a support structure in support structures
301. For example, the association of group of nozzles
304 with support structure
306 forms spray bar
308.
[0055] In these illustrative examples, properties
140 in
Figure 2 may be controlled with different levels of granularity. For example, each group of
nozzles in groups of nozzles
300 may have different values for properties
140 as compared to other groups of nozzles.
[0056] In still other illustrative examples, when more than one nozzle is in group of nozzles
304, values for properties
140 may be controlled individually for each nozzle in group of nozzles
304. In other words, one group of nozzles in groups of nozzles
300 may spray drops
132 of water
130 in
Figure 1 with a different size or range of sizes as compared to another group of nozzles in
groups of nozzles
300 through the control of properties
140 for these two groups of nozzles. In this manner, the sizes of drops
132 of water
130 may be achieved using groups of nozzles
300 to obtain a desired type of icing condition within types of icing conditions
102 in
Figure 1.
[0057] Turning now to
Figure 4, an illustration of a block diagram of an infrastructure in an icing simulation system
is depicted in accordance with an illustrative embodiment. In this illustrative example,
examples of some components that may be present in infrastructure
127 include lines
400, valves
402, and sensors
403 are shown. Lines
400 may include, for example, flexible lines
404 and rigid lines
406.
[0058] In these illustrative examples, lines
400 may be used to connect water source
124 and air source
126 to nozzle system
122 in
Figure 1. Further, some of lines
400 may be connected to cooling system
120 in
Figure 1.
[0059] Valves
402 are associated with lines
400. Valves
402 may be operated to control the flow of fluids through lines
400. In these illustrative examples, these fluids may be water
130 and air
134 in
Figure 1. In these illustrative examples, the operation of valves
402 is controlled by controller
128. Controller
128 operates valves
402 to select values for properties
140 in
Figure 1.
[0060] Sensors
403 are configured to detect the values of properties
140. Additionally, sensors
403 also may be configured to detect the position of valves
402, the flow of liquids through lines
400, and other suitable parameters.
[0061] As depicted, sensors
403 may be associated with lines
400 and valves
402. Further, sensors
403 also may be associated with nozzle system
122.
[0062] Sensors
403 generate data
408 that is sent to controller
128. Controller
128 operates valves
402 to adjust the values of properties
140.
[0063] The illustration of icing simulation environment
100 in
Figure 1 and the components of icing simulation environment
100 in
Figures 1-4 are not meant to imply physical or architectural limitations to the manner in which
an illustrative embodiment may be implemented. Other components in addition to or
in place of the ones illustrated may be used. Some components may be unnecessary.
Also, the blocks are presented to illustrate some functional components. One or more
of these blocks may be combined, divided, or combined and divided into different blocks
when implemented in an illustrative embodiment.
[0064] In some illustrative examples, one or more test objects in addition to test object
103 may be placed in test area
142 during simulation of desired type of icing condition
111 using icing simulation system
110. Also, test object
103 may take other forms other than an aircraft or objects that are for or part of an
aircraft. For example, test object
103 may be selected from one of an automobile windshield, automobile, a ship, an engine
hood, a deck of a ship, and other suitable test objects.
[0065] In still other illustrative examples, valves
402, sensors
403, or both may be considered part of controller
128. In still other illustrative examples, additional types of icing conditions in addition
to or in place of first type of icing condition
112 and second type of icing condition
114 in types of icing conditions
102 may be present. For example, in some types of icing conditions, three or more ranges
of sizes for drops
132 of water
130 may be present for those types of icing conditions.
[0066] Turning now to
Figure 5, an illustration of an icing simulation system is depicted in accordance with an
illustrative embodiment. In this depicted example, icing simulation system
500 is one example of a physical implementation for icing simulation system
110 shown in block form in
Figure 1.
[0067] In this illustrative example, a top view of icing simulation system
500 is shown. As depicted, icing simulation system
500 includes wind tunnel
502, air drive system
504, nozzle system
506, cooling system
508, and controller
510.
[0068] In this depicted example, wind tunnel
502 has turning vane
512, turning vane
514, turning vane
516, and turning vane
518. These turning vanes aid in directing air flow
520 generated by air drive system
504 to turn or curve within wind tunnel
502.
[0069] As depicted, air flow
520 is generated by air drive system
504. In this illustrative example, air drive system
504 comprises fan system
522. In this illustrative example, nozzle system
506 comprises spray bars
524.
[0070] In these illustrative examples, spray bars
524 are configured to spray drops of water
526 within wind tunnel
502. Drops of water
526 are carried by air flow
520 through test section
528 within wind tunnel
502.
[0071] In these illustrative examples, air flow
520 is cooled using cooling system
508. As depicted, cooling system
508 comprises refrigeration system
530 and heat exchanger
532. Refrigeration system
530 and heat exchanger
532 operate to cool air within air flow
520 passing by or through heat exchanger
532.
[0072] In this illustrative example, sensor system
509 takes the form of laser sensor system
534. Laser sensor system
534 sends laser beam
536 into wind tunnel
502 where drops of water
526 are generated by spray bars
524 in nozzle system
506. Laser sensor system
534 sends data about sizes of drops of water
526 to controller
510 in control room
538.
[0073] With feedback from laser sensor system
534 in sensor system
509, controller
510 may adjust properties of water sent through spray bars
524 in nozzle system
506 to obtain desired sizes for drops of water
526 to simulate a desired type of icing condition.
[0074] In these illustrative examples, drops of water
526 may have two ranges of sizes for the desired icing condition. In particular, the
desired icing condition may be a supercooled large drop icing condition. In these
illustrative examples, drops of water
526 may include sizes for normal drops and sizes for supercooled large drops.
[0075] Turning now to
Figure 6, an illustration of a spray bar balancing system is depicted in accordance with an
illustrative embodiment. As depicted, spray bar balancing system
600 may be implemented in a number of different places within icing simulation system
110 in
Figure 1. For example, spray bar balancing system
600 may be implemented as part of infrastructure
127, nozzle system
122, or a combination of the two in
Figure 1.
[0076] In this illustrative example, spray bar balancing system
600 may be used to control spray bar
602 in a manner that allows for drops
604 of water to be produced with a desired size and temperature more quickly to form
a desired icing cloud for a desired type of icing condition.
[0077] As described above, the drop size may be defined by the mean volumetric diameter
of the drops of water and/or the liquid water content in the drops of water. These
parameters are functions of the pressure of air in spray bar
602 and the change in pressure of air in spray bar
602, as well as the velocity of the drops of water within the tunnel.
[0078] In this illustrative example, spray bar
602 is comprised of support structure
605 and nozzles
606. In this example, nozzles
606 include nozzle
608, nozzle
610, nozzle
612, and nozzle
614. Support structure
605 contains water line
618 and air line
620. Water line
618 supplies water to nozzles
606, and air line
620 supplies air to nozzles
606.
[0079] In these illustrative examples, valves
622 in support structure
605 control water that passes through nozzles
606. As depicted, valves
622 include valve
624, valve
626, valve
628, and valve
630. These valves are associated with nozzle
608, nozzle
610, nozzle
612, and nozzle
614, respectively.
[0080] In these illustrative examples, support structure
605 in spray bar
602 has water input
632 and water return output
634. Additionally, support structure
605 has air input
636. Water input
632 is connected to water supply
638 by line
640. Water return output
634 is connected to water return
642 by line
644. Air input
636 is connected to air supply
646 by line
648. Needle valve
650 and bypass valve
652 are associated with line
644. Air valve
654 is associated with line
648. Pressure valve
656 is associated with line
640.
[0081] In this illustrative example, spray bar
602 may operate in a spray mode and a bypass mode. In bypass mode, spray bar
602 does not spray drops
604 of water. In this mode, valves
622 are closed and bypass valve
652 is open. In this manner, water flowing from water supply
638 may flow through water line
618 in support structure
605 of spray bar
602. This water may flow out of spray bar
602 at water return output
634 and through line
644 to water return
642.
[0082] When in the bypass mode, pressure valve
656 may be adjusted to supply water at a desired pressure level for a desired type of
icing condition. In this manner, the desired pressure may be present before switching
to a spray mode.
[0083] When spray bar
602 is placed into a spray mode, valves
622 are opened, and bypass valve
652 is closed. In the spray mode, drops
604 of water are sprayed out of nozzles
606 from spray bar
602. Drops
604 of water form an icing cloud in these illustrative examples. Drops
604 of water have properties that simulate a desired icing condition.
[0084] In spray mode, valves
622 are open to allow drops
604 of water to be sprayed out of nozzles
606. Additionally, air valve
654 and pressure valve
656 are also open. Bypass valve
652 is closed.
[0085] With air valve
654 open, air may flow from air supply
646 through line
648 into air line
620 through air input
636 to reach nozzles
606. Additionally, water may flow from water supply
638 through line
640 into water input
632 to reach nozzles
606.
[0086] In these illustrative examples, this operation of the valves may cause a change in
the pressure of the water flowing to nozzles
606. Needle valve
650 is located downstream of bypass valve
652 and is configured to balance the flow of water during the change from a bypass mode
to a spray mode. In this manner, any change in the pressure of the water may be reduced
such that the change does not affect the spraying of drops
604 of water in a manner that affects simulating the desired icing condition. In other
words, the properties of drops
604 of water may reach desired properties for the desired icing condition more quickly
with this configuration.
[0087] The different components shown in
Figures 5-6 may be combined with components in
Figures 1-4, used with components in
Figures 1-4, or a combination of the two. Additionally, some of the components in
Figures 5-6 may be illustrative examples of how components shown in block form in
Figures 1-4 can be implemented as physical structures.
[0088] With reference now to
Figure 7, an illustration of a flowchart of a process for simulating icing conditions is depicted
in accordance with an illustrative embodiment. The process illustrated in
Figure 7 may be implemented in icing simulation environment
100 in
Figure 1. In particular, the process may be implemented in icing simulation system
110.
[0089] The process begins by identifying a desired type of icing condition (operation
700). The process identifies a number of properties for water sent to a nozzle system
for the desired type of icing condition (operation
702).
[0090] Next, a test object is placed into a wind tunnel (operation
704). A number of properties for the water sent to the nozzle system is controlled (operation
706). In these illustrative examples, the number of properties is controlled such that
drops of water have sizes associated with the type of icing condition. In other words,
the values for the properties are selected such that drops of water have sizes that
are characteristic of the type of icing condition to be simulated.
[0091] For example, with a supercooled large drop icing condition, the drops of water may
include normal drops and large drops as described above. Further, the water also may
have a desired temperature that can be reached as the drops of water travel in the
wind tunnel.
[0092] Drops of water are then sprayed from the nozzle system in the wind tunnel (operation
708), with the process terminating thereafter. The drops of water sprayed by the nozzle
system have different sizes that correspond to the desired type of icing condition.
These different sizes may be different ranges, depending on the type of icing condition.
[0093] In this manner, the simulation of the icing condition in a wind tunnel allows for
a test object to be tested to see how the test object performs in the desired icing
condition. For example, sensor systems for detecting icing conditions may be tested
using this process without placing the sensors on an aircraft and flying the aircraft
into weather with the desired icing condition.
[0094] With reference now to
Figure 8, an illustration of a flowchart of a process for calibrating an icing simulation
system is depicted in accordance with an illustrative embodiment. This process may
be used to set icing simulation system
110 to produce drops
132 of water
130 with desired sizes for desired type of icing condition
111 in
Figure 1.
[0095] The process begins by identifying groups of nozzles to be processed (operation
800). The process then selects a group of nozzles from the groups of nozzles for processing
(operation
802).
[0096] The process identifies a desired size for drops sprayed by the group of nozzles (operation
804). Next, the process identifies values for one or more properties of water to be sent
through the group of nozzles (operation
806). The properties of the water are controlled to meet those values for the group of
nozzles (operation
808). Drops of water are then sprayed from the group of nozzles using the values (operation
810).
[0097] Next, the size of the drops of water is identified (operation
812). The size of the drops of water may be identified using a sensor system, such as
sensor system
123 in
Figure 1. A determination is made as to whether the size of the drops of water meet the desired
size (operation
814). The desired size may be met if the size of the drops of water identified are the
same as the desired size. In these illustrative examples, the desired size also may
be met, in some cases, if the size of the drops of water are within a range of the
desired size.
[0098] If the size of the drops of water does not meet the desired size, an adjustment to
the values of the properties needed to reach the desired size is identified (operation
816). The process then returns to operation
808.
[0099] With reference again to operation
814, if the desired size of the drops of water is met, a determination is made as to
whether an additional unprocessed group of nozzles is present in the groups of nozzles
(operation
818). If an additional unprocessed group of nozzles is present, the process returns to
operation
802. Otherwise, the process terminates.
[0100] Although this process may be used to calibrate the groups of nozzles prior to simulating
a desired type of icing condition, this process may also be used at other times. For
example, this process also may be used while the desired type of icing condition is
being simulated. The process may be used to adjust the manner in which drops of water
are sprayed such that the desired type of icing condition can be maintained even though
other parameters in the icing simulation environment may change.
[0101] The flowcharts and block diagrams in the different depicted embodiments illustrate
the architecture, functionality, and operation of some possible implementations of
apparatuses and methods in an illustrative embodiment. In this regard, each block
in the flowcharts or block diagrams may represent a module, segment, function, and/or
a portion of an operation or step. For example, one or more of the blocks may be implemented
as program code, in hardware, or a combination of the program code and hardware. When
implemented in hardware, the hardware may, for example, take the form of integrated
circuits that are manufactured or configured to perform one or more operations in
the flowcharts or block diagrams.
[0102] In some alternative implementations of an illustrative embodiment, the function or
functions noted in the blocks may occur out of the order noted in the figures. For
example, in some cases, two blocks shown in succession may be executed substantially
concurrently, or the blocks may sometimes be performed in the reverse order, depending
upon the functionality involved. Also, other blocks may be added in addition to the
illustrated blocks in a flowchart or block diagram.
[0103] Turning now to
Figure 9, an illustration of a data processing system is depicted in accordance with an illustrative
embodiment. Data processing system
900 may be used to implemented controller
128 in
Figure 1. In this illustrative example, data processing system
900 includes communications framework
902, which provides communications between processor unit
904, memory
906, persistent storage
908, communications unit
910, input/output (I/O) unit
912, and display
914. In this example, communications framework
902 may take the form of a bus system.
[0104] Processor unit
904 serves to execute instructions for software that may be loaded into memory
906. Processor unit
904 may be a number of processors, a multi-processor core, or some other type of processor,
depending on the particular implementation.
[0105] Memory
906 and persistent storage
908 are examples of storage devices
916. A storage device is any piece of hardware that is capable of storing information,
such as, for example, without limitation, data, program code in functional form, and/or
other suitable information either on a temporary basis and/or a permanent basis. Storage
devices
916 may also be referred to as computer readable storage devices in these illustrative
examples. Memory
906, in these examples, may be, for example, a random access memory or any other suitable
volatile or nonvolatile storage device. Persistent storage
908 may take various forms, depending on the particular implementation.
[0106] For example, persistent storage
908 may contain one or more components or devices. For example, persistent storage
908 may be a hard drive, a flash memory, a rewritable optical disk, a rewritable magnetic
tape, or some combination of the above. The media used by persistent storage
908 also may be removable. For example, a removable hard drive may be used for persistent
storage
908.
[0107] Communications unit
910, in these illustrative examples, provides for communications with other data processing
systems or devices. In these illustrative examples, communications unit
910 is a network interface card.
[0108] Input/output unit
912 allows for input and output of data with other devices that may be connected to data
processing system
900. For example, input/output unit
912 may provide a connection for user input through a keyboard, a mouse, and/or some
other suitable input device. Further, input/output unit
912 may send output to a printer. Display
914 provides a mechanism to display information to a user.
[0109] Instructions for the operating system, applications, and/or programs may be located
in storage devices
916, which are in communication with processor unit
904 through communications framework
902. The processes of the different embodiments may be performed by processor unit
904 using computer-implemented instructions, which may be located in a memory, such as
memory
906.
[0110] These instructions are referred to as program code, computer usable program code,
or computer readable program code that may be read and executed by a processor in
processor unit
904. The program code in the different embodiments may be embodied on different physical
or computer readable storage media, such as memory
906 or persistent storage
908.
[0111] Program code
918 is located in a functional form on computer readable media
920 that is selectively removable and may be loaded onto or transferred to data processing
system
900 for execution by processor unit
904. Program code
918 and computer readable media
920 form computer program product
922 in these illustrative examples. In one example, computer readable media
920 may be computer readable storage media
924 or computer readable signal media
926.
[0112] In these illustrative examples, computer readable storage media
924 is a physical or tangible storage device used to store program code
918 rather than a medium that propagates or transmits program code
918.
[0113] Alternatively, program code
918 may be transferred to data processing system
900 using computer readable signal media
926. Computer readable signal media
926 may be, for example, a propagated data signal containing program code
918. For example, computer readable signal media
926 may be an electromagnetic signal, an optical signal, and/or any other suitable type
of signal. These signals may be transmitted over communications links, such as wireless
communications links, optical fiber cable, coaxial cable, a wire, and/or any other
suitable type of communications link.
[0114] The different components illustrated for data processing system
900 are not meant to provide architectural limitations to the manner in which different
embodiments may be implemented. The different illustrative embodiments may be implemented
in a data processing system including components in addition to and/or in place of
those illustrated for data processing system
900. Other components shown in
Figure 9 can be varied from the illustrative examples shown. The different embodiments may
be implemented using any hardware device or system capable of running program code
918.
[0115] Illustrative embodiments of the disclosure may be described in the context of aircraft
manufacturing and service method
1000 as shown in
Figure 10 and aircraft
1100 as shown in
Figure 11. Turning first to
Figure 10, an illustration of an aircraft manufacturing and service method is depicted in accordance
with an illustrative embodiment. During pre-production, aircraft manufacturing and
service method
1000 may include specification and design
1002 of aircraft
1100 in
Figure 11 and material procurement
1004.
[0116] During production, component and subassembly manufacturing
1006 and system integration
1008 of aircraft
1100 takes place. Thereafter, aircraft
1100 may go through certification and delivery
1010 in order to be placed in service
1012. While in service
1012 by a customer, aircraft
1100 is scheduled for routine maintenance and service
1014, which may include modification, reconfiguration, refurbishment, and other maintenance
or service.
[0117] Each of the processes of aircraft manufacturing and service method
1000 may be performed or carried out by a system integrator, a third party, and/or an
operator. In these examples, the operator may be a customer. For the purposes of this
description, a system integrator may include, without limitation, any number of aircraft
manufacturers and major-system subcontractors; a third party may include, without
limitation, any number of vendors, subcontractors, and suppliers; and an operator
may be an airline, a leasing company, a military entity, a service organization, and
so on.
[0118] With reference now to
Figure 11, an illustration of an aircraft is depicted in which an illustrative embodiment may
be implemented. In this example, aircraft
1100 is produced by aircraft manufacturing and service method
1000 in
Figure 10 and may include airframe
1102 with plurality of systems
1104 and interior
1106. Examples of systems
1104 include one or more of propulsion system
1108, electrical system
1110, hydraulic system
1112, and environmental system
1114. Any number of other systems may be included. Although an aerospace example is shown,
different illustrative embodiments may be applied to other industries, such as the
automotive industry.
[0119] Apparatuses and methods embodied herein may be employed during at least one of the
stages of aircraft manufacturing and service method
1000 in
Figure 10. In one illustrative example, components or subassemblies produced in component and
subassembly manufacturing
1006 in
Figure 10 may be fabricated or manufactured in a manner similar to components or subassemblies
produced while aircraft
1100 is in service
1012 in
Figure 10.
[0120] As yet another example, one or more apparatus embodiments, method embodiments, or
a combination thereof may be utilized during production stages, such as specification
and design
1002 and system integration
1008 in
Figure 10. For example, icing simulation system
110 may be used to test various prototypes of components or structures during specification
and design
1002.
[0121] One or more apparatus embodiments, method embodiments, or a combination thereof may
be utilized while aircraft
1100 is in service
1012 and/or during maintenance and service
1014. For example, icing simulation system
110 may be used to test upgrades or changes to aircraft
1100 made during maintenance and service
1014. For example, if new or different sensor systems for detecting icing conditions are
added to aircraft
1100, icing simulation system
110 may be used to determine whether those sensors perform as desired. The use of a number
of the different illustrative embodiments may substantially expedite the assembly
of and/or reduce the cost of aircraft
1100.
[0122] Thus, one or more illustrative embodiments provide a method and apparatus for simulating
icing conditions. The simulation of the icing conditions may be used to determine
whether a test object performs as desired during different types of icing conditions.
For example, as requirements change on what types of icing conditions are required
to be detected by an aircraft, sensor systems for those types of icing conditions
may be designed and tested using an illustrative embodiment.
[0123] For example, icing simulation system
110 provides an ability to generate water drops having different sizes. In particular,
the water drops may have two ranges of sizes. These ranges may be ranges that represent
supercooled large drop icing conditions. The ranges may be generated by controlling
different spray bars within icing simulation system
110 to spray drops of water with different sizes. In this manner, the spray bars may
generate drops of water having the two desired ranges of drop sizes for supercooled
large drop icing conditions.
[0124] With icing simulation system
110, recreating a desired icing condition may reduce the amount of time needed to meet
regulations regarding the icing conditions. Further, with the use of icing simulation
system
110, the time, effort, and/or expense needed to certify an aircraft or icing detection
system may be reduced.
[0125] Of course, icing simulation system
110 may be used to generate icing conditions other than those described in the illustrative
examples. For example, other icing conditions may include three or more ranges of
drop sizes.
[0126] In the text and the figures, in one aspect, an icing simulation system is disclosed
including: a wind tunnel; a nozzle system configured to spray drops of water within
the wind tunnel; and a controller configured to control a number of properties of
the water in the nozzle system such that the nozzle system sprays the drops of the
water with different sizes for a desired type of icing condition. In one variant,
the icing simulation system includes wherein the number of properties is selected
from at least one of a water pressure, an air pressure, and a temperature. In another
variant, the icing simulation system includes wherein the nozzle system comprises
groups of nozzles.
[0127] In yet another variant, the icing simulation system includes wherein in being configured
to control the number of properties of the water in the nozzle system such that the
nozzle system sprays the drops of the water with the different sizes for the desired
type of icing condition, the controller is configured to select at least one of a
water pressure, an air pressure, and a temperature for the water for each group of
nozzles in the groups of nozzles such that the groups of nozzles spray the drops of
the water with the different sizes for the desired type of icing condition. In still
another variant, the icing simulation system includes wherein a group of nozzles in
the groups of nozzles is associated with a spray bar.
[0128] In one instance, the icing simulation system further includes: a spray bar balancing
system configured to reduce a time for the spray bar to spray the drops of the water
with a desired size.
[0129] In another instance, the icing simulation system further includes: a plurality of
valves configured to control at least one of a water pressure, an air pressure, and
a temperature for the water; and a computer system configured to control an operation
of the plurality of valves. In yet another instance, the icing simulation system further
includes: a sensor system configured to detect a size of the drops of the water. In
still yet another instance, the icing simulation system includes wherein the desired
type of icing condition is a supercooled large drop icing condition.
[0130] In one example, the icing simulation system includes wherein a second type of icing
condition includes the drops of the water having a diameter greater than about 0.111
millimeters. In another example, the icing simulation system includes wherein the
desired type of icing condition further includes additional drops of the water having
a diameter that is less than or equal to about 0.111 millimeters. In yet another example,
the icing simulation system includes wherein the wind tunnel includes a test section
configured to hold a test object. In still yet another example, the icing simulation
system of claim 12, wherein the test object is selected from one of an airfoil, an
aircraft, an engine, a wing, a horizontal stabilizer, a vertical stabilizer, a landing
gear system, a fuselage, a flap, an aircraft windshield, an automobile windshield,
an automobile, a ship, an engine hood, and a deck of a ship.
[0131] In one aspect, a method is disclosed for simulating a desired type of icing condition
in a wind tunnel, the method including: controlling a number of properties for water
sent to a nozzle system, wherein the number of properties is controlled such that
drops of the water have different sizes associated with the desired type of icing
condition; and spraying the drops of the water from the nozzle system in the wind
tunnel, wherein the drops of the water sprayed by the nozzle system have the different
sizes for the desired type of icing condition. In one variant, the method includes
wherein controlling the number of properties for the water sent to the nozzle system,
wherein the number of properties is controlled such that the drops of the water have
the different sizes associated with the desired type of icing condition includes:
controlling at least one of a water pressure, an air pressure, and a temperature for
the water sent to the nozzle system, wherein the number of properties is controlled
such that the drops of the water have the different sizes associated with the desired
type of icing condition.
[0132] In another variant, the method includes wherein spraying the drops of the water from
the nozzle system in the wind tunnel, wherein the drops of the water sprayed by the
nozzle system have the different sizes for the desired type of icing condition includes:
spraying the drops of the water from groups of nozzles in the nozzle system in the
wind tunnel, wherein the drops of the water sprayed by the nozzle system have the
different sizes for the desired type of icing condition. In yet another variant, the
method includes wherein controlling the number of properties for the water sent to
the nozzle system, wherein the number of properties is controlled such that the drops
of the water have the different sizes associated with the desired type of icing condition
includes: selecting at least one of a water pressure, an air pressure, and a temperature
for the water for each group of nozzles in the groups of nozzles such that the groups
of nozzles spray the drops of the water with the different sizes for the desired type
of icing condition.
[0133] In yet another variant, the method includes wherein spraying the drops of the water
from the groups of nozzles in the nozzle system in the wind tunnel, wherein the drops
of the water sprayed by the nozzle system have the different sizes for the desired
type of icing condition includes: spraying the drops of the water from the groups
of nozzles in the nozzle system in the wind tunnel, wherein the drops of the water
sprayed by the nozzle system have the different sizes for the desired type of icing
condition, wherein a group of nozzles in the groups of nozzles is associated with
a spray bar. In still yet another variant, the method includes wherein controlling
the number of properties for the water sent to the nozzle system, wherein the number
of properties is controlled such that the drops of the water have the different sizes
associated with the desired type of icing condition includes: controlling the number
of properties for the water sent to the nozzle system, wherein the number of properties
is controlled such that the drops of the water have the different sizes associated
with a supercooled large drop icing condition. In one instance, the method of further
includes: placing a test object in a test section of the wind tunnel, wherein the
test object is selected from one an airfoil, an aircraft, an engine, a wing, a horizontal
stabilizer, a vertical stabilizer, a landing gear system, a fuselage, a flap, an aircraft
windshield, an automobile windshield, an automobile, a ship, an engine hood, and a
deck of a ship.
[0134] The description of the different illustrative embodiments has been presented for
purposes of illustration and description, and is not intended to be exhaustive or
limited to the embodiments in the form disclosed. Many modifications and variations
will be apparent to those of ordinary skill in the art, within the scope of the appended
claims.
[0135] Although an illustrative embodiment has been described with respect to aircraft,
the illustrative embodiment may be applied to other types of platforms and structures
for those platforms. For example, without limitation, other illustrative embodiments
may be applied to a mobile platform, a stationary platform, a land-based structure,
an aquatic-based structure, a space-based structure, and/or some other suitable platform
or structure for those platforms. More specifically, the different illustrative embodiments
may be applied to, for example, without limitation, a submarine, a bus, a personnel
carrier, a tank, a train, an automobile, a spacecraft, a space station, a satellite,
a surface ship, and/or some other suitable platform.
[0136] Further, different illustrative embodiments may provide different features as compared
to other illustrative embodiments. The embodiment or embodiments selected are chosen
and described in order to best explain the principles of the embodiments, the practical
application, and to enable others of ordinary skill in the art to understand the disclosure
for various embodiments with various modifications as are suited to the particular
use contemplated, within the scope of the appended claims.